This present invention is concerned with a method for disinfection and sterilization of foods and vegetable products and produce, feeding stuffs or machinery and equipment for food and/or feeding stuff production.
A similar method is known for U.S. Pat. No. 4,849,237.
This mentioned patent specification concerns a method for desinfection of chicken bodies kept immersed in cooling water with ozone added, which water is made to move or flow in the opposite direction of the chicken's movement. The disadvantage of that known method is that the cooling water acts as contaminator from one chicken to another, and further the process may cause mean and fat to deteriorate and go rancid.
This present invention is concerned with a method for desinfection and/or sterilization of foods of all kinds for use in any part of the food or foodstuff or feeding stuff industry, by organisations, corporations, companies and institutions in the food sector, and the method described has the purpose of preventing the risk of humans or animals being exposed to infection from micro organisms or their byproducts resulting in subsequent pathological diseases or reactions, poisonings and other illnesses. Authorities and health care organisations today often report the increasing need for methods to transport, treat, process, manufacture, pack, deliver and distribute food and feeding stuffs without dangerous, poisonous, infectuous, pathological and disease-causing effects.
Most infections of the nature described in the above start or are caused by growth of micro organisms on the surfaces of food products or produce or on the surfaces of other materials or equipment able to hold and carry micro organisms.
For many years it has been a common and acknowledged practice in the industries and companies mentioned in the above text to control raw materials and production with help from authority representatives and own experts by having samples taken at intervals and in quantities stipulated for each separate production, which samples are taken checked and analysed in official, recognised and/or own laboratories. Frequently controls concentrate on checks for salmonella bacteria, which occur in some 2,000 different known types, some of which cause severe cases of illness or poisonings in humans or animals after consumption.
The consequential effects of bacteria infection and the occurrence of pathological cases have increased considerably over the past few years, presumably because of shorter production times, large quantity manufacturing and mass production, automation and mechanised control and processing, at the same time as the craftsman's job and his control during the manufacturing process has been taken over by technical installations and sporadic or statistically determined controls.
One common procedure is to take out small sample items of the processed food or feeding stuff and submit these to a laboratory for testing. Here, microorganisms are cultivated on various substrates (nutritious media) and after 3 or 4 days growths of bacteria or micro organisms may be found. Next the decision has to be taken whether the growths have to be subjected to further special analysis, which can only be dealt with by large, specialised laboratories with adequate equipment, and the bacteria samples are therefore sent to such special laboratories causing added cost and time delays.
Food articles or feeding stuffs are sampled from manufacturing plants immediately after processing, or they are sent away for freezing, and therefore results of such testing is often only available several days later than dispatch due to industry requirements for quick processing and short warehouse periods.
A few types of Salmonella and other bacteria provoke serious cases of disease. Acute gastroeneritis would be caused by e.g. Salmonella Typhi Murium or Enteriditis. More serious cases are caused by bacteria such as Salmonella Paratyphi type A, B or C and also by Salmonella Dublini, which infections may be mortal. Salmonella Typhi especially is the cause of the infectuous typhoid disease which may cause death from poisoning or mass epidemics in humans under certain conditions.
It is a known fact that many such cases of infection are not reported to public authorities so that they do not appear in statistics, but in medical circles the assumption is that the number of diseases, poisonings or other cases may be counted in hundreds of thousands per year globally, and mortal cases are reported to be several thousands every year.
One recently registered patent, EP No: 0 299 601 (Al) indicates that the invention described may certify the occurrence of Salmonella infection within 24 hours, thus reducing the time needed for analysis and testing, but the method of the invention does not prevent or preclude any such infection.
The existence of micro organisms or bacteria in or on foods or feeding stuffs is dangerous to consumers since neither cooling nor freezing result in bactericidal processes, sterilization or desinfection. During transportation, delivery, commercial distribution and warehousing in cooled, refrigerated or frozen conditions the bacteria growth comes to a standstill, but subsequent use or application will enable the bacteria to cause renewed growth under favourable temperatures and conditions.
Salmonella bacteria are surface bacteria which will, if subjected to favourable temperatures in the surroundings and to nutrient substrates in the form of foods or feeding stuffs, multiply through duplication every 20 minutes, which means that the Salmonella bacteria count should be multiplied by a factor larger than 10.sup.21 for every 24 hours, enabling the the huge number of infectuous matter to spread easily in the processing environment through human hand, transportation, cutting, manufacture, processing and storage.
Traditionally, people in the profession have over time taken care to this risk in all concerned industries and services, and bacteria growth and the spreading of micro organisms have been prevented by cleaning and sanitation, but the precautions taken have not been sufficient to prevent infection and the occurrence of pathological events, especially gastroenteritis or stomach poisonings, and authorities, companies engaged in food processing or feeding stuff production, corporations, distributors and other manufacturing or servicing units have not been able to offer the public and the consumers sterilised products free of the risk of the infections indicated in the above.